EP2779893A1 - Électrogrammes pour identifier une morphologie de bloc de branche - Google Patents

Électrogrammes pour identifier une morphologie de bloc de branche

Info

Publication number
EP2779893A1
EP2779893A1 EP12794610.1A EP12794610A EP2779893A1 EP 2779893 A1 EP2779893 A1 EP 2779893A1 EP 12794610 A EP12794610 A EP 12794610A EP 2779893 A1 EP2779893 A1 EP 2779893A1
Authority
EP
European Patent Office
Prior art keywords
duration
threshold value
qrs
activation
indication
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP12794610.1A
Other languages
German (de)
English (en)
Inventor
Barun Maskara
Shibaji Shome
Pramodsingh Hirasingh Thakur
Abhilash Patangay
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Cardiac Pacemakers Inc
Original Assignee
Cardiac Pacemakers Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Cardiac Pacemakers Inc filed Critical Cardiac Pacemakers Inc
Publication of EP2779893A1 publication Critical patent/EP2779893A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/68—Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient
    • A61B5/6846—Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient specially adapted to be brought in contact with an internal body part, i.e. invasive
    • A61B5/6847—Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient specially adapted to be brought in contact with an internal body part, i.e. invasive mounted on an invasive device
    • A61B5/686—Permanently implanted devices, e.g. pacemakers, other stimulators, biochips
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/316—Modalities, i.e. specific diagnostic methods
    • A61B5/318—Heart-related electrical modalities, e.g. electrocardiography [ECG]
    • A61B5/346—Analysis of electrocardiograms
    • A61B5/349—Detecting specific parameters of the electrocardiograph cycle
    • A61B5/366—Detecting abnormal QRS complex, e.g. widening
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/316—Modalities, i.e. specific diagnostic methods
    • A61B5/318—Heart-related electrical modalities, e.g. electrocardiography [ECG]
    • A61B5/346—Analysis of electrocardiograms
    • A61B5/349—Detecting specific parameters of the electrocardiograph cycle
    • A61B5/352—Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/74—Details of notification to user or communication with user or patient ; user input means
    • A61B5/746—Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00—Electrotherapy; Circuits therefor
    • A61N1/18—Applying electric currents by contact electrodes
    • A61N1/32—Applying electric currents by contact electrodes alternating or intermittent currents
    • A61N1/36—Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
    • A61N1/362—Heart stimulators
    • A61N1/3627—Heart stimulators for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy

Definitions

  • Implantable medical devices include devices designed to be implanted into a patient.
  • Some examples of these implantable medical devices include cardiac function management (CFM) devices such as implantable pacemakers, implantable cardioverter-defibrillators (ICDs), cardiac resynchronization therapy devices (CRTs), or devices that include a combination of these capabilities or others.
  • CFM cardiac function management
  • the devices can be used to treat patients or subjects using electrical or other therapies, or to aid a physician or caregiver in patient diagnosis through monitoring of a patient condition.
  • the devices can include one or more electrodes in communication with one or more sense amplifiers to monitor electrical heart activity within a patient, and can include one or more sensors to monitor one or more other internal patient parameters.
  • Other examples of IMDs include implantable diagnostic devices, implantable drug delivery systems, or implantable devices with neural stimulation capability.
  • medical devices also include other ambulatory medical devices, such as wearable medical devices (WMDs), such as wearable cardioverter defibrillators (WCDs).
  • WCDs can include monitors that can include surface electrodes.
  • the surface electrodes can be arranged to provide one or both of monitoring surface electrocardiograms (ECGs) or delivering cardioversion or defibrillation shock therapy.
  • ECGs monitoring surface electrocardiograms
  • Some medical devices can include one or more sensors to monitor a physiologic status of a patient.
  • a device can be configured to measure a cardiac depolarization of the patient, a thoracic impedance, or a patient posture, among other things. Such measurements can provide useful information concerning the health of the patient, such as can be used to indicate a therapy.
  • a problem to be solved can include identifying ventricular cardiac dysfunction.
  • ventricular cardiac dysfunction can include left or right bundle branch block, or intraventricular conduction delay.
  • the present subject matter can provide a solution to this problem, such as by using one or more electrogram signals to provide an indication of ventricular dysfunction or to help distinguish between different types of ventricular dysfunction.
  • a patient QRS duration can be received or determined from a patient electrogram (e.g., an electrocardiogram), such as can be obtained using one or more implanted or external patient physiological sensors.
  • the QRS complex morphology can represent the health of the myocardium, including the left and right sides.
  • the QRS duration can be extended, such as indicating a delayed activation of a portion of the myocardium (e.g., one of the left or right side) relative to a different portion of the myocardium (e.g., the other one of the left or right side).
  • a portion of the QRS duration can be determined, such as a right or left ventricular activation time.
  • the right ventricular activation time can be determined by identifying an onset of a QRS complex and a corresponding R-wave peak in the QRS complex, such as using an electrogram obtained using an electrode disposed in or near the right ventricle.
  • an indication of a cardiac conduction dysfunction can be provided.
  • FIGS. 1A and IB illustrate generally a relationship between a patient success rate and various cardiac therapies.
  • FIG. 2 illustrates generally an example of a system that can include an ambulatory medical device and an external module.
  • FIG. 3 illustrates generally an example that can include an implantable medical device and an implantable lead system, including leads disposed in a heart.
  • FIG. 4 illustrates generally an example of a system that can include a processor circuit, a processor-readable medium, and a cardiac signal sensing circuit.
  • FIGS. 5A and 5B illustrate generally examples that can include device- based electrograms.
  • FIG. 6 illustrates generally an example of Q-RV interval information from several patients.
  • FIG. 7 illustrates generally an example that can include identifying left ventricular conduction dysfunction.
  • FIG. 8 illustrates generally an example that can include identifying left ventricular conduction dysfunction.
  • FIG. 9 illustrates generally an example that can include identifying right ventricular conduction dysfunction.
  • FIG. 10 illustrates generally an example that can include providing an indication of cardiac conduction dysfunction.
  • FIGS. 11A and 1 IB illustrate generally examples that can include providing an indication of cardiac conduction dysfunction.
  • FIG. 12 illustrates generally an example of monitoring an indication of a patient cardiac status.
  • FIG. 13 illustrates generally an example that can include monitoring a patient physiological status.
  • FIGS. 1A and IB illustrate generally a relationship between a patient success rate and various cardiac therapies.
  • cardiac conduction dysfunction such as a right bundle branch block (RBBB), left bundle branch block (LBBB), or intraventricular conduction delay (IVCD).
  • RBBB right bundle branch block
  • LBBB left bundle branch block
  • IVCD intraventricular conduction delay
  • Such dysfunction can be caused by an underlying heart disease or myocardial infarction, among other causes.
  • Bundle branch block can affect one or both sides of the myocardium, and can be indicated by a delay or obstruction of the natural electrical impulses that can cause a healthy heart to contract.
  • IVCD can similarly be associated with an electrical conduction delay.
  • Some conditions that can lead to bundle branch block or IVCD can include one or more of myocardial infarction, or cardiomyopathy, among others, such as without a specific indication of a left or right bundle branch block.
  • FIG. 1A illustrates generally an example 100 of an average patient success rate over time for patients who do not exhibit a bundle branch block (e.g., a left bundle branch block), such as in first and second patient populations.
  • a bundle branch block e.g., a left bundle branch block
  • the first patient population such represented using a first trendline 151a, can include patients who have available cardiac
  • resynchronization therapy and defibrillation (CRT-D) treatments such as using an implantable CRT-D device.
  • the second patient population such as represented using a second trendline 152a, can include patients who have available only implantable cardiac defibrillation (ICD) treatments.
  • ICD implantable cardiac defibrillation
  • a non-left bundle branch block (non-LBBB) patient with a CRT-D device can be approximately equally likely to experience heart failure or death as a non-LBBB patient with an ICD device.
  • FIG. IB illustrates generally an example 150 of an average patient success rate over time for patients who exhibit a bundle branch block (e.g., a left bundle branch block).
  • a probability of patient heart failure or death can be compared for first and second populations, such as a first patient population that has CRT-D therapies available (represented using a third trendline 151b), and a second patient population that has ICD therapies available (represented using a fourth trendline 152b).
  • a left bundle branch block (LBBB) patient with a CRT-D device can be substantially less likely to experience heart failure or death than a LBBB patient with an ICD device only. That is, a LBBB patient who has a device that can provide both cardiac resynchronization therapy and defibrillation can be more likely to avoid heart failure and death than a patient who has a device that provides only cardioversion and defibrillation therapies. Patients can therefore benefit from an identification of bundle branch block cardiac morphologies. For example, where a LBBB morphology is identified in a patient, the patient can be a candidate for receiving a cardiac resynchronization device.
  • an ICD device can be used to monitor one or more patient cardiac signals, and can be used to provide an indication that the patient is a candidate for cardiac resynchronization therapy, such as when a particular BBB morphology is indicated.
  • FIG. 2 illustrates generally an example of a system 200 that can include an implantable medical device (HVID) 105 or other ambulatory medical device, such as can be used to provide an indication of, or provide therapy for, a bundle branch block.
  • the HVID 105 can include a cardiac rhythm management device, or pacemaker, such as can be configured to deliver a cardiac resynchronization therapy such as to a diseased heart.
  • the IMD 105 can include a cardioverter-defibrillator, among other implantable medical devices.
  • the IMD 105 can be disposed in or into a subject body 101, and the IMD 105 can be communicatively coupled to an external module 1 15.
  • the IMD 105 can include an antenna configured to provide radio-frequency or other wireless communication between the IMD 105 and the external module 115, or other external device.
  • the IMD 105 can include one or more of a cardiac stimulating circuit, a cardiac signal sensing circuit, or a processor circuit, such as described below in the discussion of FIG. 4.
  • a functional portion of one or more of the cardiac stimulating circuit, cardiac signal sensing circuit, or the processor circuit can be located in the IMD 105, and another portion elsewhere (e.g., in an external programmer or analyzer circuit, such as in the external module 1 15).
  • the external module 1 15 can include a local medical device programmer or other local external module, such as within wireless communication range of the IMD 105 antenna.
  • the external module 1 15 can include a remote medical device programmer or one or more other remote external modules (e.g., outside of wireless communication range of the IMD 105 antenna, but coupled to the IMD 105 using a local external device, such as a repeater or network access point).
  • the external module 115 can include a processor circuit that can be configured to process information that can be sent to or received from the IMD 105.
  • the information can include medical device programming information, subject data, device data, or other instructions, indications, alerts, or other information.
  • the external module 1 15 can be configured to display information (e.g., received information) to a user, such as a patient or a clinician, such as using a local patient interface. Further, the local programmer or the remote programmer can be configured to communicate the sent or received information to a user or physician, such as by sending an alert or indication via email of the status of the subject 101 or the system 200 components. In an example, the external module 115 can adjust a therapy control signal, such as can be used by the processor circuit of the IMD 105 to control a patient therapy, such as a drug or electrostimulation therapy.
  • a therapy control signal such as can be used by the processor circuit of the IMD 105 to control a patient therapy, such as a drug or electrostimulation therapy.
  • FIG. 3 illustrates generally an example of a system 300 that can include the IMD 105.
  • the IMD 105 can include an implantable electronics unit 106, such as can include a processor circuit 110, a motion detector 104, or a drive/sense circuit 121.
  • the implantable electronics unit 106 can include a housing 103 (or attached header) that can include one or more conductive portions that can optionally serve as an electrode (e.g., a "can" or "header” electrode), or the electronics unit 106 can be electrically and physically coupled to an implantable lead system 108.
  • an electrode e.g., a "can" or "header” electrode
  • Portions of the implantable lead system 108 can be inserted into a patient's thorax, such as intravascularly into or epicardially onto a patient heart 107.
  • the implantable lead system 108 can include one or more cardiac pace/sense electrodes (e.g., one or more of the electrodes 113, 114, 1 16, 1 18, 126, or 128, among others), such as can be positioned in, on, or about one or more heart chambers such as can be configured to sense one or more electrical signals from the patient heart 107.
  • Intracardiac sensing and pacing electrodes such as those shown in FIG. 3, can be used to sense or pace one or more chambers of the heart, such as the left ventricle (LV), the right ventricle ( V), the left atrium (LA), or the right atrium (RA).
  • the implantable lead system 108 can include one or more defibrillation electrodes (e.g., coil electrodes 1 11 and 1 12), such as for delivering defibrillation or cardioversion shocks to the heart 107, or for sensing one or more intrinsic electrical signals from the heart 107.
  • the tip electrode 128 can be used to receive right ventricular electrogram information.
  • Other defibrillation electrodes can be used to receive electrical activity information (e.g., electrograms) corresponding to one or more other portions of the heart 107.
  • the implantable lead system 108 and the electronics unit 106 of the IMD 105 can be configured to sense a QRS complex in a cardiac signal segment.
  • the implantable lead system 108 can include one or more other physiological sensors.
  • the implantable lead system 108 can include a pressure sensor 1 19, such as can be disposed on an endocardial lead to monitor hemodynamic changes, such as a variation in pressure within a right ventricle of the heart 107.
  • the pressure sensor 119 can include a transducer, such as including a piezo-resistive element that can be mounted on a silicon diaphragm such as behind a compliant membrane window.
  • a communications circuit can be included within the housing 103 (or attached header), such as to facilitate communication between the electronics unit 106 and the external module 115.
  • the communications circuit can facilitate unidirectional or bidirectional communication with one or more implanted, ambulatory, external, cutaneous, or subcutaneous physiologic or non-physiologic sensors, patient-input devices, or information systems.
  • the motion detector 104 can be used to sense patient physical activity or one or more respiratory or cardiac related conditions.
  • the motion detector 104 can be configured to sense a patient physical activity level or chest wall movements associated with respiratory effort.
  • the motion detector 104 can include a single-axis or multiple-axis (e.g., three-axis) accelerometer that can be located in or on the housing 103.
  • An accelerometer can be used to provide information about changes in patient posture, respiratory information including, for example, about rales or coughing, cardiac information including, for example, S1-S4 heart sounds, murmurs, or other acoustic information.
  • an accelerometer can be used to detect activity information about an aortic valve 130 or a mitral valve 131.
  • a storage circuit can be included, such as within the housing 103, such as for storing a plurality of values, such as including data trend information.
  • the storage circuit can be used to store information about a cardiac signal, such as duration information, including information about a QRS duration, a right ventricular activation duration, or a left ventricular activation duration.
  • a right or left ventricular activation duration can include an interval that can begin at or before an onset of a QRS complex (e.g., when a P or Q wave is indicated), and can terminate at some portion of an indication of right or left ventricular activity, such as an R-wave peak, or an R- wave amplitude that exceeds a particular threshold value, such as can be derived or specified using electrogram information associated with a right or left ventricle of the heart 107.
  • a QRS complex e.g., when a P or Q wave is indicated
  • the drive/sense circuit 121 can be configured to generate a current that flows through body tissue, such as between an impedance drive electrode (e.g., cardiac pace/sense electrodes 1 13) and a can electrode on the housing 103 of the electronics unit 106.
  • an impedance drive electrode e.g., cardiac pace/sense electrodes 1 13
  • a can electrode on the housing 103 of the electronics unit 106 In response to such a drive or excitation signal, a voltage at an impedance sense electrode 114 relative to the can electrode can be detected, and such response voltage can change as the patient's thoracic impedance changes.
  • the response voltage signal developed between the impedance sense electrode 114 and the can electrode can be detected by the drive/sense circuit 121.
  • information about thoracic or cardiac impedance can be used to determine, among other things, heart rate or other cardiac activity information. Locations or combinations of sense or drive electrodes other than those illustrated in FIG. 3 are possible.
  • FIG. 4 illustrates generally an example of a system 400 that can include a processor circuit 110, a processor-readable medium 109, and a cardiac signal sensing circuit 120.
  • the processor circuit 1 10 can be configured to include or access the processor-readable medium 109, such as to retrieve instructions that can be used by the processor circuit 110 such as to control the cardiac signal sensing circuit 120.
  • the processor circuit 110 can include one or more outputs, such as can be configured to provide information to the processor-readable medium 109 or to provide information to a
  • the processor circuit 1 10 can include one or more inputs, such as can be configured to receive information from the cardiac signal sensing circuit 120 or the processor-readable medium 109, among other sources.
  • the cardiac signal sensing circuit 120 can be configured to sense a cardiac signal segment that can include a QRS complex.
  • the QRS complex can be analyzed, such as using the processor circuit 1 10.
  • Information about the QRS complex such as information about a width, or duration, of all or a designated other portion of the QRS complex, can be processed using the processor circuit 1 10, which can be configured to report or make available the information to an external device (e.g., the external module 115, an external programmer, directly to a clinician's handheld mobile device, email, etc.).
  • the processor circuit 1 10 can be configured to provide the QRS information for a plurality of cardiac cycles or physical activity levels.
  • the processor circuit 1 10 can count, trend, or store the QRS information, such as in a histogram.
  • the histogram can be used to store information about a number or frequency of occurrences of detected features of a QRS complex, such as a width of a designated portion of a QRS complex, or a differential relationship that can include a designated portion of a QRS complex, among other relationships.
  • the cardiac signal sensing circuit 120 can be electrically coupled to the implantable lead system 108, or one or more other electrodes.
  • the cardiac signal sensing circuit 120 can include a sense amplifier, and a sampling circuit, such as can be configured to sense an electrogram signal using the implantable lead system 108.
  • the cardiac signal sensing circuit 120 can include a unipolar or bipolar sensing channel, such as including or coupled to a sense electrode and a reference electrode.
  • the terms "bipolar” and “unipolar” refer to a number of electrodes that can be disposed in the vicinity of the heart.
  • a bipolar sensing channel configuration can include two electrodes that can be in contact with the heart or are intracardiac.
  • a unipolar configuration can include a first electrode that can be in contact with the heart, intracardiac, or generally nearer the heart than the second electrode, which can be disposed remotely from the first electrode, such as at the housing of a pectorally or abdominally implanted device. Sensing the cardiac signal segment using a unipolar sensing configuration can, in some examples, provide additional information regarding a ventricular depolarization, or other thoracic activity, as compared to using a bipolar sensing configuration.
  • the implantable lead system 108 can include multipolar electrode leads that can be disposed in or associated with one or more of the left or right ventricles of the heart.
  • a right ventricular lead can include a tip electrode 128, a ring electrode 118, a shock electrode 112, or one or more other electrodes.
  • RV activation duration information can be determined using electrogram information received using a bipolar electrode configuration, such as including the tip electrode 128 and the ring electrode 118, among other bipolar configurations.
  • the RV activation duration information can be determined using electrogram information that can be received using a unipolar electrode configuration, such as using the tip electrode 128, or the shock electrode 1 12, among other unipolar configurations.
  • the cardiac signal sensing circuit 120 can include a plurality of inputs or outputs.
  • the circuit can include a first input 201, such as can be coupled to a physiological sensor 204.
  • the cardiac signal sensing circuit 120 can include other inputs and outputs 202, 203, such as can be coupled to one or more electrodes (e.g., the implantable lead system 108) that can be configured to deliver electrostimulation therapy or to receive information about cardiac electrical activity (e.g., an electrogram signal).
  • the cardiac signal sensing circuit 120 can be configured to receive electrical information from in or near the heart, for example, over at least a portion of a cardiac or respiratory cycle, such as using one or more of the physiological sensor 204 or the electrodes coupled to the inputs and outputs 202, 203, among other sensors.
  • the electrical information can include an impedance waveform, an electrical cardiogram (ECG) signal (e.g., an evoked response, a subcutaneous ECG, or other signal), an electrical signal from a heart sound sensor such as a microphone, an electrical signal from an accelerometer configured to provide an indication of mechanical cardiac activity, an electrical signal from a pressure sensor configured to provide an indication of a pressure, such as a central venous pressure (CVP), a right ventricle pressure, a coronary vein pressure, or one or more other electrical signals indicative of cardiac information.
  • ECG electrical cardiogram
  • a heart sound sensor such as a microphone
  • an accelerometer configured to provide an indication of mechanical cardiac activity
  • an electrical signal from a pressure sensor configured to provide an indication of a pressure, such as a central venous pressure (CVP), a right ventricle pressure, a coronary vein pressure, or one or more other electrical signals indicative of cardiac information.
  • CVP central venous pressure
  • the processor circuit 110 can include a peak detector circuit, a QRS complex duration timer circuit, or a bundle branch block (BBB) detector circuit, among others.
  • the processor circuit 110 can use the peak detector circuit to determine a time of a maxima and a time of a minima in a sensed cardiac signal segment, such as during an identified QRS complex.
  • BBB bundle branch block
  • the processor circuit 110 can be configured to identify a duration of a QRS complex. For example, the circuit can identify at least a Q time in a cardiac signal segment, and can identify an S time in the cardiac signal segment. In an example, the processor circuit 110 can determine a time duration of the QRS complex in the cardiac signal segment using the identified Q time and S time. In an example, the Q time can be identified using the processor circuit 1 10 to determine an isoelectric amplitude value of the cardiac signal segment. Isoelectric amplitude values can be determined from sampled values of the sensed cardiac signal segment, and an isoelectric value of the signal can be defined to be zero volts or an amplitude of a substantially "flat" portion of the cardiac signal segment. In an example, the processor circuit 1 10 can identify, as a Q time in the QRS complex, a time at which the cardiac signal segment amplitude deviates from the isoelectric amplitude value by at least a specified threshold deviation value.
  • the processor circuit 1 10 can be configured to determine an isoelectric value time, after the determined maxima and minima times, when the cardiac signal segment returns to the same or a different isoelectric amplitude value.
  • the S time in the QRS complex can be identified as the time that follows both the determined maxima and minima times and precedes the isoelectric value time.
  • the cardiac signal segment amplitude at the identified S time can satisfy a specified amplitude change criterion from an isoelectric amplitude value. Examples of identifying an S time are described in Patangay et al., U.S. Pat. App. No.
  • the processor circuit 110 can be configured to determine one or more portions of the QRS complex.
  • the processor circuit 1 10 can be configured to determine a Q-RV interval, such as an RV activation duration.
  • the duration information can be used to determine an abnormal cardiac signal morphology, such as by comparing a portion of the QRS complex (e.g., the Q-RV interval) to an overall QRS complex duration.
  • FIGS. 5A and 5B illustrate generally examples that can include device- based electrogram signals.
  • the electrograms in FIGS. 5A and 5B can be determined such as using the system 300.
  • FIG. 5A illustrates an example of several time-aligned electrograms that can be used to provide an indication of an abnormal cardiac signal morphology, such as a bundle branch block morphology.
  • the electrograms 51 1, 521, 531 of FIG. 5 A can be obtained, such as using the IMD 105 or the system 300.
  • FIG. 5A illustrates that can include device- based electrogram signals.
  • the electrograms in FIGS. 5A and 5B can be determined such as using the system 300.
  • FIG. 5A illustrates an example of several time-aligned electrograms that can be used to provide an indication of an abnormal cardiac signal morphology, such as a bundle branch block morphology.
  • the electrograms 51 1, 521, 531 of FIG. 5 A can be obtained, such as using the IMD 105 or the
  • the system 300 can include a right ventricular rate electrode (e.g., an electrode configured to deliver a unipolar pacing therapy to a right ventricle, such as using the tip electrode 128), or a left ventricular rate electrode (e.g., an electrode configured to deliver a bipolar pacing therapy to a left ventricle, such as using the tip electrode 126 or ring electrode 1 16), among others.
  • these electrodes or others, such as together with the IMD 105 can be used to measure electrograms indicative of cardiac electrical activity (e.g., device-based electrograms).
  • the right ventricular rate electrode can be used to obtain a first RV electrogram 51 1
  • the left ventricular rate electrode can be used to obtain a first LV electrogram 521.
  • Any number of electrograms can be obtained and time-aligned, such as shown in FIGS. 5A and 5B, for further analysis.
  • other electrodes or electrode configurations can be used to obtain electrograms, such as using one or any combination of the electrodes in the implantable lead system 108.
  • the shock electrode 1 12 can be used to obtain a shock electrogram.
  • an additional electrode such as a surface electrode disposed on the patient body 101, can be used to obtain a surface ECG electrogram 531.
  • At least one electrogram can be used to determine an onset of a QRS complex, such as a Q time.
  • the surface ECG electrogram 531 can be used to determine an indication of the Q time 540, such as by identifying a deviation from an isoelectric amplitude value, such as described above.
  • Other electrograms can be used to determine the Q time 540, such as an electrogram obtained using the shock electrode 1 12, or an electrogram obtained using one or more other electrodes (e.g., other electrodes in the implantable lead system 108, or other surface electrodes, such as one or more electrodes used in a 12 lead ECG).
  • At least one electrogram can be used to determine an R- wave of the QRS complex.
  • at least one electrogram can be used to identify a feature of the R-wave, such as an onset, peak, or inflection point, among other features, of the R-wave.
  • the first RV electrogram 51 1 can be used to determine a peak 542 of the R-wave (e.g., a first dominant peak in the electrogram).
  • the R-wave or R-wave feature can be identified using one or more of electrograms 511, 521, or 531, such as using the processor circuit 110.
  • the same electrogram can be used to identify the onset of a QRS complex (e.g., a Q time) and the R- wave or feature of the R-wave.
  • the duration of a QRS complex or a portion of a QRS complex can be used to provide an indication of cardiac dysfunction.
  • a QRS complex can provide information representative of both right and left sides of the myocardium, and, where the QRS complex is wide, or extended in duration relative to a normal QRS complex, particular portions of the myocardium that are delayed relative to the other portions can be identified. For example, where right ventricular activation occurs normally relative to a wide QRS complex, LBBB can be indicated.
  • the processor circuit 110 can be used to identify a Q-RV interval 501 as a period beginning at the Q time 540 and ending at the R-wave peak 542.
  • the Q-RV interval 501 can provide an indication of a cardiac ventricular dysfunction when the interval is less than a particular threshold duration.
  • the Q-RV interval 501 can be about 13 ms, and can indicate LBBB where the overall QRS complex duration is extended, or wide, relative to a normal patient state (e.g., a QRS complex duration that exceeds about 100 ms).
  • FIG. 5B illustrates generally several electrograms that can be used to provide an indication of an abnormal patient cardiac morphology, such as right bundle branch block (RBBB) or an intraventricular conduction delay (IVCD) morphology.
  • IVCD can be any non-specific block, such as may affect both sides of the myocardium.
  • the electrograms of FIG. 5B can be obtained, such as according to the description of FIG. 5 A, or they can be obtained using different electrode configurations.
  • the electrograms can include a second RV electrogram 512, a second LV
  • any one of the electrograms 512, 522, or 532, among other electrograms can be used to identify an onset of a QRS complex, or can be used to identify an R-wave or a portion of an R-wave, such as an R-wave feature (e.g., peak, inflection point, threshold amplitude, etc.).
  • the second surface ECG electrogram 532 can be used to determine an indication of the Q time 544
  • the second RV electrogram 512 can be used to determine an indication of the R-wave peak 546.
  • the processor circuit 110 can be used to identify a second Q-RV interval 502.
  • the second Q-RV interval 502 can be a period beginning at a time corresponding with the Q time 544 and ending at a time corresponding with the R-wave peak 546.
  • the Q-RV interval 502 can provide an indication of RBBB or IVCD when the interval is greater than a threshold duration.
  • the Q-RV interval 502 can be about 87 ms, and can indicate RBBB or IVCD where the overall QRS complex duration is extended, or wide, relative to a normal QRS width.
  • a QRS complex, QRS duration, or a portion of the QRS duration can be determined using other physiological sensors 204 (e.g., sensors configured to provide information other than electrogram signal information), such as can be configured to provide heart sound information, or other information indicative of heart tissue or valve activity.
  • sensors 204 e.g., sensors configured to provide information other than electrogram signal information
  • a point other than a Q time can be used as a reference point, such as for determining an RV or LV activation duration.
  • an accelerometer can be used to receive information about an AV valve closure (e.g., corresponding to an R-wave peak in an electrogram), or to receive information about a mitral or aortic valve opening or closing (e.g., to indicate an S I or S2 heart sound, respectively).
  • an AV valve closure e.g., corresponding to an R-wave peak in an electrogram
  • a mitral or aortic valve opening or closing e.g., to indicate an S I or S2 heart sound, respectively.
  • a Q time or similar reference point such as in combination with electrogram information.
  • an RV activation duration can be representative of a time duration between at least one of (1) an aortic valve or mitral valve closure and (2) an R-wave peak.
  • the valve closures can be indicated using one or more heart sound sensors, and the R-wave peak can be identified in an right ventricular electrogram.
  • FIG. 6 illustrates generally an example of Q-RV interval information from about 30 patients.
  • the Q-RV interval information in the example of FIG. 6 was obtained using an external 12 lead ECG.
  • patients with LBBB tend to have a Q-RV interval of about 10 to 50 ms
  • patients with RBBB or IVCD tend to have a Q-RV interval of about 50 to 120 ms. Therefore, by identifying a patient's Q-RV interval, such as relative to an overall QRS complex width, patients with dysfunctional cardiac conduction morphologies can be identified.
  • FIG. 7 illustrates generally an example 700 that can include identifying left ventricular conduction dysfunction.
  • FIG. 7 illustrates generally how information derived from an electrogram, such as can be obtained using an electrode coupled to an implantable cardioverter-defibrillator or other device, can be used to determine if a patient exhibits a left bundle branch block cardiac signal morphology.
  • a left bundle branch block can be indicated using a relative comparison of a right ventricular activity indication and a portion of a QRS complex duration.
  • identifying a left bundle branch block can indicate that the patient is a candidate for a cardiac resynchronization therapy device.
  • a QRS width can be estimated, such as using one or more of the techniques described above in the discussion of FIG. 5A, among others.
  • a cardiac signal e.g., an electrogram
  • the QRS width estimation can be performed using the processor circuit 110 to identify an interval between a Q time and S time of the cardiac signal.
  • the QRS width can be estimated from previously-recorded patient data.
  • the estimated QRS width can be compared to a first threshold value to determine if the QRS complex is extended relative to a normal patient QRS complex width, such as using the processor circuit 110.
  • a normal patient QRS complex width can generally be less than about 100 ms.
  • the QRS complex does not exceed the first threshold value, then the patient can be identified as not an ideal candidate for cardiac resynchronization therapy, at 725.
  • the patient can be identified as being at low risk for LBBB, RBBB, or IVCD, or other dysfunction associated with extended QRS width.
  • the first threshold value can be determined using patient-specific information, such as using QRS complex duration information obtained from a patient chart (e.g., using information about a previously-acquired ECG) or electronic medical record (EMR).
  • QRS complex duration information obtained from a patient chart (e.g., using information about a previously-acquired ECG) or electronic medical record (EMR).
  • EMR electronic medical record
  • the first threshold value can be more than about 100 ms, such as about 120 ms.
  • the QRS width can exceed the first threshold value, such as can be determined using the processor circuit 1 10.
  • a right ventricular (RV) activation duration, or Q-RV interval can be measured at 730, such as according to the discussion of FIGS. 5A and 5B, above.
  • the processor circuit 1 10 can be used to analyze an electrogram to identify the RV activation duration.
  • the RV activation duration can be determined using previously- recorded patient data.
  • the RV activation duration can be analyzed, such as using the processor circuit 1 10.
  • the RV activation duration can be compared to a second threshold value (e.g., a threshold value specified to be between about 40 and 50 ms).
  • the second threshold value can be determined using patient-specific information, such as using QRS complex duration information obtained from a patient. If the RV activation duration exceeds the second threshold value, RBBB or IVCD can be indicated at 745. If the RV activation duration does not exceed the second threshold value, a left ventricular conduction dysfunction, such as LBBB, can be indicated at 755.
  • a ratio or other relative indication of the RV activation duration to a QRS duration can be compared to a third threshold value. If the ratio exceeds the third threshold value, RBBB or IVCD can be indicated at 745. If the ratio does not exceed the third threshold value, or the RV activation duration is less than the second threshold value, then LBBB can be indicated at 755.
  • the second threshold value can be specified to be about 45 ms
  • the third threshold value can be specified to be between about 0.2 and 0.4. Other specified threshold values can be used as well, such as corresponding to a particular patient cardiac morphology.
  • the third threshold value can be specified using previously-acquired patient data, such as patient-specific data including information about a patient RV activation duration or a patient QRS width.
  • the RV activation duration measured at 730 can be used to provide an indication of RBBB or IVCD.
  • RBBB or IVCD can be provided without using information about the overall patient QRS width.
  • RV activation duration is extended relative to a normal RV activation duration
  • RBBB or IVCD can be indicated.
  • the normal activation duration can be determined using other, previously-acquired patient data, such as patient-specific data including information obtained from an external 12 lead ECG.
  • At least one of the IMD 105 or the external module 1 15 can be used to provide an alert or indication, such as that a patient is at low risk for LBBB, RBBB, or IVCD (e.g., at 725), to provide an alert or indication that a patient exhibits an RBBB or IVCD morphology, or to provide an alert or indication that a patient exhibits left ventricular conduction dysfunction.
  • the alert or indication can be provided to a user, such as the patient or a clinician, such as according to the discussion of FIG. 1, above.
  • one or more therapies such as an electrostimulation or drug therapy, can be triggered in response to an identification of RBBB or IVCD at 745, or an identification of left ventricular conduction dysfunction at 755.
  • FIG. 8 illustrates generally an example 800 that can include providing an indication of a left ventricular conduction dysfunction.
  • information about a QRS duration can be received or determined.
  • an RV activation duration can be received or determined, such as before determining whether the QRS duration exceeds a first threshold value at 830.
  • the example of FIG. 8 can be used to provide an indication of RBBB at 822, such as before performing the comparison at 830.
  • the information about the QRS duration and the RV activation duration can be received or determined according to the discussion of FIG. 7, above.
  • the RV activation duration can be compared to a second threshold value at 842, such as according to the discussion at 740. If the RV activation duration does not exceed the second threshold value (e.g., 45 ms), an indication of left ventricular conduction dysfunction (e.g., LBBB) can be provided at 855.
  • a second threshold value e.g. 45 ms
  • a differential relationship between the RV activation duration and the QRS duration can be determined at 844.
  • the differential relationship can include, among other relationships, a ratio or a difference of the
  • the differential relationship can be compared to a third threshold value and, if the differential relationship is less than the third threshold value, an indication of a left ventricular conduction dysfunction (e.g., LBBB) can be provided.
  • a left ventricular conduction dysfunction e.g., LBBB
  • FIG. 9 illustrates generally an example 900 that can include providing an indication of a right ventricular conduction dysfunction.
  • information about a QRS duration can be received or determined.
  • an RV activation duration can be received or determined at 920, such as using the information about the QRS duration received at 912.
  • the information about the QRS duration can be determined using an electrogram, such as can be received using a shock electrode disposed in the heart 107.
  • the information about the QRS duration and the RV activation duration can be determined such as by analyzing the electrogram, such as according to the discussion of FIGS. 5A and 5B.
  • the QRS duration (e.g., obtained at 912) can be compared to a first threshold value at 930. If the QRS duration exceeds the first threshold value (e.g., about 120 ms), then the RV activation duration can undergo further analysis. In an example, if the QRS duration does not exceed the first threshold value, a normal patient QRS width can be indicated and the analysis can terminate.
  • a first threshold value e.g., about 120 ms
  • the RV activation duration can be compared to a second threshold value at 943, and, when the RV activation duration exceeds the second threshold value, an indication of a right ventricular conduction dysfunction can be provided at 957.
  • the right ventricular conduction dysfunction can include RBBB or IVCD.
  • a differential relationship between the RV activation duration and the QRS duration can be determined (e.g., a ratio of the RV activation duration to the QRS duration).
  • the differential relationship can be compared to a third threshold value.
  • the third threshold value e.g., where the differential relationship is a ratio of the RV activation duration to the QRS duration, the third threshold value can be selected to be about 0.3
  • an indication of right ventricular conduction dysfunction can be provided.
  • the indication of right ventricular conduction dysfunction provided at 957 can be provided even if information about a QRS duration is not available.
  • the information about the RV activation duration such as received or determined at 920, can be used to identify RBBB or IVCD patients.
  • FIG. 10 illustrates generally an example 1000 that can include providing an indication of at least one of left bundle branch block, right bundle branch block, or intraventricular conduction delay.
  • information about a QRS duration can be received or determined at 1012, such as according to the discussion of FIG. 7.
  • the QRS duration can be compared to a first threshold value at 1020, such as according to the discussion of FIG. 7 at 720.
  • an RV activation duration can be determined at 1030.
  • the RV activation duration can be compared to one or more threshold values, and the comparison can be used to provide, among other things, an indication of at least one of LBBB, RBBB, or IVCD.
  • the indication of at least one of RBBB or IVCD can be provided when (1) the QRS duration exceeds the first threshold value, and (2) the RV activation duration exceeds a second threshold value.
  • the indication of LBBB can be provided when (1) the QRS duration exceeds the first threshold value, and (2) the RV activation duration is less than the second threshold value.
  • an LV activation duration can be determined at 1031.
  • the LV activation duration can be determined using one or more electrodes disposed in association with the left ventricle of the heart 107, such as in a patient having an implantable cardiac resynchronization therapy device coupled to a left ventricular lead.
  • the LV activation duration can be compared to one or more specified threshold values, and the comparison can be used to provide, among other things, an indication of LBBB.
  • information about the LV activation duration can be used for other patient screening, diagnostic, or therapy control, such as to indicate if a patient is non-responsive to therapy, if a patient cardiac conduction pattern has changed, or for other screening, diagnostic, or therapy control purpose.
  • information about the LV activation duration can be used to identify a cardiac signal morphology or a change in a cardiac signal morphology, such as can be used to detect an ischemic episode.
  • the LV and RV activation durations can be used, at 1060, such as together with information about the QRS duration, such as to provide an indication of one or more of LBBB, RBBB, or IVCD.
  • RV or LV activation duration information can be determined using electrogram information that can be received using multipolar electrode leads.
  • a multipolar electrode lead disposed in or near a right ventricle can be configured to receive information from multiple bipolar or unipolar sensing configurations.
  • two or more electrograms can be used to determine at least one of an RV or LV activation duration.
  • using more than one electrogram can improve the accuracy of a bundle branch block or IVCD indication, or can be used to better characterize a patient cardiac signal morphology, such as using electrogram signals received from multiple locations in or near the heart 107.
  • first RV electrogram information can be received using a bipolar configuration comprising the ring electrode 118 and the tip electrode 128.
  • second RV electrogram information can be received, such as using a second bipolar configuration, or using a unipolar configuration, such as comprising a second ring electrode and a can electrode (e.g., a conductive portion of the housing 103).
  • the first and second RV electrogram information can be compared, such as to verify that specified features (e.g., an R-wave peak) of the first and second RV electrograms correspond, such as in time or in magnitude.
  • QRS duration information or RV activation information can be determined using each of the first and second electrograms, among others, and the information can be compared, averaged, or otherwise analyzed, such as prior to performing any of the examples of FIGS. 7-11.
  • any number of electrograms or other ECG information can be obtained and compared to verify or further analyze QRS duration information or RV or LV activation duration information.
  • the processor circuit 110 can be configured to receive multiple signals or electrograms from one or more multipolar electrode leads (e.g., in the implantable lead system 108).
  • information about a cardiac activation sequence can be detected using the multipolar leads, such as using leads disposed in the left and right ventricles of the heart 107.
  • the information about the cardiac activation sequence can be used to characterize a cardiac morphology, such as to provide an indication of BBB or IVCD.
  • a first lead can be disposed in or near the right ventricle, and can receive an indication of right ventricular cardiac activity at a first time.
  • An indication of left ventricular cardiac activity can be received at a second time, such as using a second lead disposed in or near the left ventricle.
  • a difference or differential relationship between the first and second times can be used to provide the indication of BBB or IVCD.
  • FIG. 1 1A illustrates generally an example 1 100 that can include providing an indication selected from a group that includes candidate indications of left ventricular conduction dysfunction, right ventricular conduction dysfunction, or intraventricular conduction dysfunction.
  • a QRS duration and at least one of an RV activation duration or an LV activation duration, can be received or determined, such as at 11 12, 1130, and 1131, such as according to the discussion of FIG. 10, above.
  • the RV activation duration can be used, such as together with information about a QRS duration, to provide an indication of left ventricular conduction dysfunction at 1155, such as according to the discussion of FIG. 8.
  • at least one of the RV activation duration, or the ratio or other differential relationship of the RV activation duration to the QRS duration can be compared to corresponding second and third threshold values, such as at 1142 and 1 144, respectively.
  • second and third threshold values such as at 1142 and 1 144
  • an indication of intraventricular conduction dysfunction can be provided at 1 159.
  • an indication of intraventricular conduction dysfunction can be provided at 1 159.
  • an indication of right ventricular conduction dysfunction can be provided at 1 157.
  • an indication of right ventricular conduction dysfunction can be provided at 1157.
  • the LV activation duration can be used, such as together with information about a QRS duration, to provide an indication of left ventricular conduction dysfunction at 1155.
  • at least one of the LV activation duration, or the ratio of the LV activation duration to the QRS duration can be compared to corresponding fourth and fifth threshold values, such as at 1162 and 1 164, respectively.
  • fourth and fifth threshold values such as at 1162 and 1 164, respectively.
  • an indication of intraventricular conduction dysfunction can be provided at 1 159.
  • an indication of intraventricular conduction dysfunction can be provided at 1 159.
  • an indication of right ventricular conduction dysfunction can be provided at 1 157.
  • an indication of right ventricular conduction dysfunction can be provided at 1157.
  • FIG. 1 IB illustrates generally an example 11 10 that can include providing an indication of intraventricular conduction dysfunction.
  • a QRS duration, and LV and RV activation durations can be received or determined, such as at 1 112, 1130, and 1 131, such as according to the discussion of FIG. 10, above.
  • the indication of intraventricular conduction dysfunction can be provided at 1 159 when at least first and second conditions are met.
  • the first condition can be determined at 1 149. If the RV activation duration is greater than a second threshold value, or if the ratio of the RV activation duration to the QRS duration is greater than a third threshold value, the first condition can be satisfied.
  • the second condition can be determined at 1169. If the LV activation duration is greater than a fourth threshold value, or if the ratio of the LV activation duration to the QRS duration is greater than a fifth threshold value, the second condition can be satisfied. In an example in which both the first and second conditions are satisfied (i.e., at 1149 and 1 169), an indication of intraventricular conduction dysfunction can be provided at 1 159.
  • FIG. 12 illustrates generally an example that can include monitoring an indication of a patient cardiac status.
  • a chart 1200 can include a trendline 1201 that can be used to track a ratio or other differential relationship of a patient Q-RV interval to the patient QRS duration, such as over multiple cardiac cycles or other periods (e.g., the periods 1 through 10 indicated on the chart 1200).
  • the trendline 1201 can indicate the ratio at discrete times.
  • a ratio of a patient Q-RV interval to the patient QRS duration of about 0.4 can be associated with a first time, such as corresponding to an average patient Q-RV interval and QRS duration on a first day.
  • a ratio of about 0.35 can be associated with a third time, such as corresponding to an average patient Q-RV interval and QRS duration on a third day.
  • the time axis can correspond to intra-day Q-RV interval or QRS duration information (e.g., interval or duration information obtained every cardiac cycle, every minute, or every hour, etc.), or inter-day Q- RV interval or QRS duration information (e.g., interval or duration information obtained daily, weekly, monthly, etc.).
  • the IMD 105 e.g., an implantable ICD, CRT-D, or other device
  • the external module 1 15 can include a processor circuit (e.g., the processor circuit 1 10) configured to receive information about a patient Q-RV interval, the patient QRS duration, and corresponding time information.
  • the received information can be stored in memory, such as in a histogram, and the information can be analyzed either continuously, recurrently, or periodically (e.g., daily, weekly, monthly, etc.) to detect a change in the ratio of a patient Q- RV interval to the patient QRS duration.
  • the trendline 1201 can be used to identify a trend in a ratio or other differential relationship of a patient Q-RV interval to the patient QRS duration.
  • a decreasing ratio can indicate a patient trend toward bundle branch block morphology (see, for example, the discussion at FIGS. 7-11 for various examples that explain how a patient Q-RV interval and QRS duration can be used to indicate a cardiac conduction dysfunction).
  • the trendline 1201 can be monitored, and an indication or alert can be provided (e.g., using the IMD 105 or the external module 1 15) if the ratio is less than a threshold interval 1202 (e.g., about 0.3).
  • a change in the ratio or other differential relationship can indicate a patient cardiac dysfunction.
  • a sudden change can indicate an ischemic episode, such as can be due to a bundle branch block cardiac dysfunction.
  • an ischemic episode can be indicated at time 8 (e.g., corresponding to day 8, or hour 8, etc.) of Q-RV interval and QRS duration monitoring, such as where the ratio has changed by more than 0.1 relative to an adjacent data point.
  • one or more of an RV or LV activation duration, ratio, or other relationship can be monitored, such as over multiple cardiac cycles or other periods (e.g., periods corresponding to the periods in the chart 1200 or other periods).
  • Such monitoring can be used to establish one or more trendlines that can indicate a patient cardiac function status. For example, when any one or more of the trendlines exceeds a particular threshold, or changes by a particular threshold rate, one or more therapies can be initiated or otherwise adjusted, or one or more alerts or indications can be provided, such as to a patient or clinician or other user, such as using the external module 115.
  • a lengthening of a patient Q-RV interval over a first duration can indicate an ischemic episode related to a right bundle branch.
  • a stable patient Q-RV interval over a second duration such as relative to an increasing patient QRS duration over the second duration, can indicate an ischemic episode related to a left bundle branch.
  • a lengthening of a patient Q-LV interval over a third duration can indicate an ischemic episode related to a left bundle branch.
  • a stable patient Q-LV interval over a fourth duration such as relative to an increasing patient QRS duration over the fourth duration, can indicate an ischemic episode related to a right bundle branch.
  • FIG. 13 illustrates generally an example that can include adjusting a specified threshold value or providing an indication of ventricular dysfunction using information about a patient physiological status.
  • One or more threshold values can be used to determine a right or left ventricular conduction dysfunction, such as according to the discussion of FIGS. 7-11.
  • one or more of the threshold values can be adjusted, such as in response to a change in a patient physiological status.
  • patient physiological status can include a patient activity level, heart rate, respiration rate, minute ventilation, blood pressure, or posture, among others.
  • Information about the patient physiological status can be received using one or more of various physiological sensors, such as can include an implantable lead, accelerometer, microphone, or impedance sensor, such as disposed on or in the IMD 105, or coupled to the implantable lead system 108, among other sensors.
  • heart rate information can be received at 1301, such as using information received from one or more patient physiological sensors.
  • Some patients can exhibit a heart rate-dependent cardiac conduction block (e.g., a heart rate-dependent left or right bundle branch block) where a normal bundle branch cardiac signal morphology is exhibited at a baseline heart rate (e.g., in a resting state), but an abnormal bundle branch morphology is exhibited when the heart rate exceeds the baseline (e.g., when heart rate is elevated, such as due to an artificial atrial pacing therapy, or exercise, among other causes).
  • an indication of a heart rate-dependent cardiac conduction dysfunction can be provided at 1305.
  • at least one of a QRS duration interval, Q-RV interval, or Q-LV interval can be monitored, such as at one or more heart rates, such as according to the discussion of FIGS. 7-1 1. If there is a change in one or more of the QRS, Q-RV, or Q-LV intervals, such as corresponding to a change in a patient heart rate, an indication of heart rate- dependent cardiac conduction dysfunction can be provided.
  • the heart rate information received at 1301 can be compared to a heart rate threshold value at 1302.
  • the heart rate threshold value can be a specified threshold value, such as a patient-specific threshold value determined using patient ECG information.
  • the heart rate information does not exceed the heart rate threshold value and other analyses can proceed at 1303 (e.g., without adjusting a threshold value).
  • proceeding to other analyses can include, among other scenarios, proceeding according to the discussion of FIG. 7, at 710; proceeding according to the discussion of FIG. 8, at 812; proceeding according to the discussion of FIG. 9, at 912; proceeding according to the discussion of FIG. 10, at 1012; or proceeding according to the discussion of FIG. 11, at 1 112.
  • the first threshold value such as can be used to indicate an extended QRS width in the example of FIG. 7, at 720, can be adjusted at 1304, such as in response to information about a patient heart rate.
  • the first threshold value can be adjusted at 1304 in response to information about one or more other patient physiological status indications, such as a patient posture indication.
  • one or more other threshold values can be adjusted at 1304.
  • any of the first, second, third, fourth, or fifth threshold values such as explained above in the discussion of FIGS. 7-11, can be adjusted in response to a change in a patient physiological status.
  • any one or more of the indications of right or left ventricular dysfunction e.g., right or left bundle branch block, or
  • intraventricular conduction delay can be determined using information obtained from patients who have ICD devices that record patient cardiac signal information. For example, a paper or electronic patient report, such as including information about RV or LV activation duration, can be used to determine if a patient has a ventricular dysfunction, such as according to the analyses described above. In an example, the report can be retrieved from a comprehensive patient management system, such as to enable remote screening of ICD patients, such as to identify patients who can benefit from cardiac resynchronization therapy. In an example, the analyses described above can be implemented in the IMD 105, or the external module 1 15, or some other programmer, such as can be used by a clinician at patient follow-ups.
  • Example 1 includes subject matter (such as an apparatus) comprising a processor circuit that can be configured to receive or determine a QRS duration representative of a time duration of a QRS complex, and receive or determine an RV activation duration representative of a time duration between (1) an onset of the QRS complex, and (2) an R-wave in a right ventricle.
  • the processor circuit of Example 1 can be configured to determine whether the QRS duration exceeds a first threshold value and, when the QRS duration exceeds the first threshold value, the processor circuit of Example 1 can be configured to determine at least one of: (1) whether the RV activation duration is shorter than a second threshold value, and (2) whether a ratio or differential relationship of the RV activation duration to the QRS duration is less than a third threshold value.
  • the processor circuit of Example 1 can be configured to provide an indication of left ventricular conduction dysfunction when it is determined that (1) the RV activation duration is shorter than second threshold value, or (2) the ratio or differential relationship of the RV activation duration to the QRS duration is less than the third threshold value.
  • Example 2 the subject matter of Example 1 can optionally include a processor circuit configured to provide an indication of left ventricular conduction dysfunction to indicate Left Bundle Branch Block (LBBB), as distinguished from Right Bundle Branch Block (RBBB) or Intraventricular Conduction Delay (IVCD), when it is determined that an RV activation duration is shorter than a second threshold value, or when it is determined that a ratio of the RV activation duration to a QRS duration is less than a third threshold value.
  • LBBB Left Bundle Branch Block
  • RBBB Right Bundle Branch Block
  • IVCD Intraventricular Conduction Delay
  • the second threshold value of Example 2 can be specified to be about 45 milliseconds, and the third threshold value of Example 2 can be specified to be about 0.3.
  • the RV activation duration can represent a time duration between an onset of the QRS complex and an R-wave peak in a right ventricle.
  • Example 3 the subject matter of one or any combination of Examples
  • 1 -2 can optionally include a processor circuit configured to determine whether a QRS duration exceeds a first threshold value and, when the QRS duration exceeds the first threshold value, determine whether an RV activation duration is shorter than a second threshold value, and provide an indication of left ventricular conduction dysfunction when it is determined that the RV activation duration is shorter than the second threshold value.
  • a processor circuit configured to determine whether a QRS duration exceeds a first threshold value and, when the QRS duration exceeds the first threshold value, determine whether an RV activation duration is shorter than a second threshold value, and provide an indication of left ventricular conduction dysfunction when it is determined that the RV activation duration is shorter than the second threshold value.
  • Example 4 the subject matter of one or any combination of Examples 1 -3 can optionally include a processor circuit configured to determine whether a QRS duration exceeds a first threshold value and, when the QRS duration exceeds the first threshold value, determine whether a ratio or differential relationship of an RV activation duration interval to the QRS duration is less than a third threshold value, and provide an indication of left ventricular conduction dysfunction when it is determined that the ratio or differential relationship of the RV activation duration to the QRS duration is less than the third threshold value.
  • a processor circuit configured to determine whether a QRS duration exceeds a first threshold value and, when the QRS duration exceeds the first threshold value, determine whether a ratio or differential relationship of an RV activation duration interval to the QRS duration is less than a third threshold value, and provide an indication of left ventricular conduction dysfunction when it is determined that the ratio or differential relationship of the RV activation duration to the QRS duration is less than the third threshold value.
  • Example 5 the subject matter of one or any combination of Examples 1 -4 can optionally include a processor circuit configured to determine whether a QRS duration exceeds the first threshold value and, when the QRS duration exceeds the first threshold value, determine whether a ratio of an RV activation duration to the QRS duration is less than a third threshold value, and provide an indication of left ventricular conduction dysfunction when it is determined that the ratio of the RV activation duration to the QRS duration is less than the third threshold value.
  • a processor circuit configured to determine whether a QRS duration exceeds the first threshold value and, when the QRS duration exceeds the first threshold value, determine whether a ratio of an RV activation duration to the QRS duration is less than a third threshold value, and provide an indication of left ventricular conduction dysfunction when it is determined that the ratio of the RV activation duration to the QRS duration is less than the third threshold value.
  • Example 6 the subject matter of one or any combination of Examples 1-5 can optionally include a processor circuit configured to provide an indication of left ventricular conduction dysfunction to indicate Left Bundle Branch Block
  • LBBB Right Bundle Branch Block
  • IVCD Intraventricular Conduction Delay
  • RBBB Right Bundle Branch Block
  • ICD Intraventricular Conduction Delay
  • Example 8 the subject matter of one or any combination of Examples 1-7 can optionally include a processor circuit configured to determine a QRS duration using a signal obtained from a cardioversion or defibrillation shock electrode.
  • Example 9 the subject matter of one or any combination of Examples 1 -8 can optionally include a processor circuit configured to determine whether a QRS duration exceeds a first threshold value, and the first threshold value is specified between about 110 ms and about 135 ms.
  • Example 10 the subject matter of one or any combination of
  • Examples 1-9 can optionally include a processor circuit configured to determine whether an RV activation duration is shorter than a second threshold value, and the second threshold value is specified between about 40 ms and about 50 ms.
  • Example 1 the subject matter of one or any combination of
  • Examples 1-10 can optionally include a processor circuit configured to determine whether a ratio of an RV activation duration to a QRS duration is less than a third threshold value, and the third threshold value is specified between about 0.2 and about 0.4.
  • Example 12 the subject matter of one or any combination of
  • Examples 1-1 1 can optionally include a processor circuit configured to use trended information about at least one of an RV activation duration, a ratio or differential relationship of the RV activation duration to a QRS duration, or an indication of left ventricular conduction dysfunction, to generate an alert or to adjust a therapy control signal.
  • a processor circuit configured to use trended information about at least one of an RV activation duration, a ratio or differential relationship of the RV activation duration to a QRS duration, or an indication of left ventricular conduction dysfunction, to generate an alert or to adjust a therapy control signal.
  • Example 13 the subject matter of Example 12 can optionally include generating an alert that is configured to indicate at least one of myocardial ischemia or myocardial infarction, such as in response to a rate of change over a specified period of time of trended information.
  • the trended information can include information about at least one of an RV activation duration, a ratio or differential relationship of the RV activation duration to a QRS duration, or an indication of left ventricular conduction dysfunction.
  • Example 14 the subject matter of one or any combination of
  • Examples 1-13 can optionally include a processor circuit configured to use heart rate information to adjust at least one of a first threshold value, a second threshold value, or a third threshold value, or to provide a heart rate dependent indication of left ventricular conduction dysfunction.
  • a processor circuit configured to use heart rate information to adjust at least one of a first threshold value, a second threshold value, or a third threshold value, or to provide a heart rate dependent indication of left ventricular conduction dysfunction.
  • Example 15 the subject matter of one or any combination of
  • Examples 1-14 can optionally include a processor circuit configured to receive or determine an RV activation duration, wherein the RV activation duration is representative of a time duration between a heart valve closure and an R-wave peak in a right ventricle.
  • Example 16 the subject matter of one or any combination of
  • Examples 1-15 can optionally include a processor circuit configured to provide an indication of left ventricular conduction dysfunction using an activation sequence across multiple electrodes.
  • Example 17 the subject matter of one or any combination of
  • Examples 1-16 can optionally include a processor circuit configured to provide an indication of Right Bundle Branch Block (RBBB) or Intraventricular Conduction Delay (IVCD) when it is determined that an RV activation duration is longer than a second threshold value.
  • RBBB Right Bundle Branch Block
  • IVCD Intraventricular Conduction Delay
  • Example 18 includes subject matter (such as an apparatus) comprising a processor circuit configured to receive or determine a QRS duration
  • QRS complex and (2) an R-wave in a right ventricle, and receive or determine an LV activation duration representative of a time duration between (1) an onset of the QRS complex, and (2) an R-wave in a left ventricle.
  • Example 18 can optionally include a processor circuit configured to determine whether the QRS duration exceeds a first threshold value and, when the QRS duration exceeds the first threshold value, determine at least one of: (1) whether the RV activation duration is shorter than a second threshold value, (2) whether a ratio or differential relationship of the RV activation duration to the QRS duration is less than a third threshold value, (3) whether the LV activation duration is longer than a fourth threshold value, and (4) whether a ratio or differential relationship of the LV activation duration to the QRS duration is greater than a fifth threshold value.
  • a processor circuit configured to determine whether the QRS duration exceeds a first threshold value and, when the QRS duration exceeds the first threshold value, determine at least one of: (1) whether the RV activation duration is shorter than a second threshold value, (2) whether a ratio or differential relationship of the RV activation duration to the QRS duration is less than a third threshold value, (3) whether the LV activation duration is longer than a fourth threshold value, and (4) whether a ratio or differential relationship of the LV activ
  • Example 18 can optionally include a processor circuit configured to provide an indication of left ventricular conduction dysfunction when it is determined that (1) the RV activation duration is shorter than second threshold value, (2) the LV activation duration is longer than fourth threshold value, (3) the ratio or differential relationship of the RV activation duration to the QRS duration is less than the third threshold value, or (4) the ratio or differential relationship of the LV activation duration to the QRS duration is greater than the fifth threshold value.
  • a processor circuit configured to provide an indication of left ventricular conduction dysfunction when it is determined that (1) the RV activation duration is shorter than second threshold value, (2) the LV activation duration is longer than fourth threshold value, (3) the ratio or differential relationship of the RV activation duration to the QRS duration is less than the third threshold value, or (4) the ratio or differential relationship of the LV activation duration to the QRS duration is greater than the fifth threshold value.
  • Example 19 the subject matter of Example 18 can optionally include a processor circuit configured to provide an indication of Right Bundle Branch Block (RBBB) when it is determined that an LV activation duration is shorter than a fourth threshold value.
  • RBBB Right Bundle Branch Block
  • Example 20 includes subject matter (such as an apparatus) comprising a processor circuit configured to receive or determine a QRS duration
  • a QRS complex representative of a time duration of a QRS complex, determine whether the QRS duration exceeds a first threshold value, receive or determine an RV activation duration representative of a time duration between (1) an onset of the QRS complex, and (2) an R-wave in a right ventricle, receive or determine an LV activation duration representative of a time duration between (1) an onset of the QRS complex, and (2) an R-wave in a left ventricle, and when the QRS duration exceeds the first threshold value, provide an indication of at least one of Left Bundle Branch Block (LBBB), Right Bundle Branch Block (RBBB), and Intraventricular Conduction Delay (IVCD), using the RV activation duration and the LV activation duration.
  • LBBB Left Bundle Branch Block
  • RBBB Right Bundle Branch Block
  • IVCD Intraventricular Conduction Delay
  • present inventors also contemplate examples in which only those elements shown or described are provided. Moreover, the present inventors also contemplate examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), either with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein.
  • Method examples described herein can be machine or computer- implemented at least in part. Some examples can include a computer- or processor-readable medium or other machine-readable medium, such as can be encoded with instructions operable to configure an electronic device to perform methods as described in the above examples.
  • An implementation of such methods can include code, such as microcode, assembly language code, a higher-level language code, or the like. Such code can include computer- readable instructions for performing various methods. The code may form portions of computer program products. Further, in an example, the code can be tangibly stored on one or more volatile, non-transitory, or non-volatile tangible computer-readable media, such as during execution or at other times.
  • Examples of these tangible computer-readable media can include, but are not limited to, hard disks, removable magnetic disks, removable optical disks (e.g., compact disks and digital video disks), magnetic cassettes, memory cards or sticks, random access memories (RAMs), read only memories (ROMs), and the like.

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Cardiology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Molecular Biology (AREA)
  • Pathology (AREA)
  • Engineering & Computer Science (AREA)
  • Biomedical Technology (AREA)
  • Physics & Mathematics (AREA)
  • Medical Informatics (AREA)
  • Biophysics (AREA)
  • Surgery (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Physiology (AREA)
  • Electrotherapy Devices (AREA)

Abstract

Selon l'invention, une durée QRS de patient peut être reçue ou déterminée, telle qu'à l'aide d'un ou plusieurs capteurs physiologiques de patient. Une partie de la durée QRS peut être déterminée, telle qu'un temps d'activation de ventricule droit ou gauche. Selon un exemple, le temps d'activation de ventricule droit peut être déterminé par identification d'une apparition d'un complexe QRS et d'un pic d'onde R dans le complexe QRS. Selon un exemple, lorsque la durée QRS dépasse une durée seuil, et que le temps d'activation de ventricule droit ne dépasse pas une seconde durée seuil, une indication d'un dysfonctionnement de conduction cardiaque peut être fournie, telle que pour effectuer une discrimination entre un bloc de branche gauche et un bloc de branche droit.
EP12794610.1A 2011-11-16 2012-11-15 Électrogrammes pour identifier une morphologie de bloc de branche Withdrawn EP2779893A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201161560445P 2011-11-16 2011-11-16
PCT/US2012/065273 WO2013074787A1 (fr) 2011-11-16 2012-11-15 Électrogrammes pour identifier une morphologie de bloc de branche

Publications (1)

Publication Number Publication Date
EP2779893A1 true EP2779893A1 (fr) 2014-09-24

Family

ID=47263599

Family Applications (1)

Application Number Title Priority Date Filing Date
EP12794610.1A Withdrawn EP2779893A1 (fr) 2011-11-16 2012-11-15 Électrogrammes pour identifier une morphologie de bloc de branche

Country Status (3)

Country Link
US (1) US8954138B2 (fr)
EP (1) EP2779893A1 (fr)
WO (1) WO2013074787A1 (fr)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU2016355338B2 (en) * 2015-11-20 2019-04-18 Cardiac Pacemakers, Inc. Single pass coronary venous lead for multiple chamber sense and pace
EP3787493B1 (fr) * 2018-05-04 2023-04-05 University Health Network Système et procédé d'évaluation de composants qrs et probabilité de réponse à la thérapie de resynchronisation cardiaque
US11266845B2 (en) 2019-01-28 2022-03-08 Ebr Systems, Inc. Devices, systems, and methods for cardiac resynchronization therapy
CN110522442B (zh) * 2019-08-16 2022-07-08 广州视源电子科技股份有限公司 多导联心电异常检测装置、电子设备和存储介质
US11559241B2 (en) 2019-10-01 2023-01-24 Pacesetter, Inc. Methods and systems for reducing false declarations of arrhythmias
CN111449647B (zh) * 2020-03-18 2023-05-02 广州视源电子科技股份有限公司 一种心电图识别方法、装置、存储介质及电子设备
CN111449646B (zh) * 2020-03-18 2023-05-02 广州视源电子科技股份有限公司 一种心电图识别方法、装置、存储介质及电子设备
US11439812B2 (en) * 2020-06-03 2022-09-13 Sigmasense, Llc. Array operative to perform distributed/patterned sensing and/or stimulation across patient bodily section
US11964160B2 (en) 2020-07-27 2024-04-23 Medtronic, Inc. Method and apparatus for delivering bundle branch pacing
US11911622B2 (en) 2020-09-22 2024-02-27 Medtronic, Inc. Conduction system pacing with adaptive timing to maintain AV and interventricular synchrony

Family Cites Families (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5527347A (en) 1995-02-21 1996-06-18 Medtronic, Inc. Dual chamber pacing system and method with automatic adjustment of the AV escape interval for treating cardiomyopathy
US5683426A (en) 1996-08-29 1997-11-04 Pacesetter, Inc. Apparatus and method for detecting the progression of AV nodal block and atrial capture
US6129744A (en) 1997-12-04 2000-10-10 Vitatron Medical, B.V. Cardiac treatment system and method for sensing and responding to heart failure
US6370427B1 (en) 1998-07-23 2002-04-09 Intermedics, Inc. Method and apparatus for dual chamber bi-ventricular pacing and defibrillation
US7395216B2 (en) 1999-06-23 2008-07-01 Visicu, Inc. Using predictive models to continuously update a treatment plan for a patient in a health care location
US6622040B2 (en) 2000-12-15 2003-09-16 Cardiac Pacemakers, Inc. Automatic selection of stimulation chamber for ventricular resynchronization therapy
US7181285B2 (en) * 2000-12-26 2007-02-20 Cardiac Pacemakers, Inc. Expert system and method
US7076287B2 (en) 2000-12-29 2006-07-11 Ge Medical Systems Information Technologies, Inc. System and method for detecting new left bundle branch block for accelerating treatment of acute myocardial infarction
US6993389B2 (en) 2001-03-30 2006-01-31 Cardiac Pacemakers, Inc. Identifying heart failure patients suitable for resynchronization therapy using QRS complex width from an intracardiac electrogram
US6766189B2 (en) 2001-03-30 2004-07-20 Cardiac Pacemakers, Inc. Method and apparatus for predicting acute response to cardiac resynchronization therapy
US6804555B2 (en) 2001-06-29 2004-10-12 Medtronic, Inc. Multi-site ventricular pacing system measuring QRS duration
US6668194B2 (en) 2001-07-16 2003-12-23 Medtronic, Inc. Method and apparatus for monitoring conduction times in a bi-chamber pacing system
US7113823B2 (en) 2001-10-26 2006-09-26 Cardiac Pacemakers, Inc. Morphology-based optimization of cardiac resynchronization therapy
US6871096B2 (en) 2001-10-26 2005-03-22 Medtronic, Inc. System and method for bi-ventricular fusion pacing
US7283863B2 (en) 2002-04-29 2007-10-16 Medtronic, Inc. Method and apparatus for identifying cardiac and non-cardiac oversensing using intracardiac electrograms
US7123954B2 (en) 2002-09-19 2006-10-17 Sanjiv Mathur Narayan Method for classifying and localizing heart arrhythmias
US7930026B2 (en) 2003-04-25 2011-04-19 Medtronic, Inc. Monitoring QRS complex to identify left ventricular dysfunction
AR047851A1 (es) 2004-12-20 2006-03-01 Giniger Alberto German Un nuevo marcapasos que restablece o preserva la conduccion electrica fisiologica del corazon y un metodo de aplicacion
US7283864B2 (en) 2005-02-10 2007-10-16 Cardiac Pacemakers, Inc. Method and apparatus for identifying patients with wide QRS complexes
US7912544B1 (en) * 2007-04-20 2011-03-22 Pacesetter, Inc. CRT responder model using EGM information
US8090443B2 (en) 2008-09-15 2012-01-03 Xiaoyi Min Monitoring HF exacerbation and cardiac resynchronization therapy performance
US8676304B2 (en) 2009-11-24 2014-03-18 Angel Medical Systems, Inc. Ischemia monitoring system for patients having periods of left bundle branch block
US9713432B2 (en) 2011-05-31 2017-07-25 Cardiac Pacemakers, Inc. Wide QRS detector

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2013074787A1 *

Also Published As

Publication number Publication date
WO2013074787A1 (fr) 2013-05-23
US8954138B2 (en) 2015-02-10
US20130123653A1 (en) 2013-05-16

Similar Documents

Publication Publication Date Title
US10702167B2 (en) Method to trigger storage of onset of physiologic condition in an implantable device
US10542902B2 (en) Atrial fibrillation detection
US8954138B2 (en) Using device based electrograms to identify bundle branch block morphology
US11304646B2 (en) Systems and methods for detecting atrial tachyarrhythmia using heart sounds
AU2017308071B2 (en) Diastolic endocardial accelerations for heart failure monitoring
CN111093758B (zh) 用于心力衰竭管理的系统
US10617320B2 (en) Method to trigger an atrial fibrillation electrogram in an implantable device that detects R-waves
US10201289B2 (en) Measuring atrial fibrillation burden using implantable device based sensors
US9295405B2 (en) SV/CO trending via intracardiac impedance
US10166001B2 (en) Trending S1 heart sounds amplitudes in ambulatory patients for worsening HF detection
EP2731499B1 (fr) Appareils de prédiction de remodelage ventriculaire
EP3720348B1 (fr) Détection de rythmes cardiaques lents et persistants
US10945670B2 (en) Minute volume sensor optimization using quadripolar leads
US20200179706A1 (en) Hemodynamically optimized rate response pacing using heart sounds

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20140613

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Effective date: 20180904